The present invention relates to apparatus and a method for securing a pane of a window or door against impact.
It is known to apply window safety film, commonly called applied window film, to the inside face of window panes to prevent glass shattering. Such applied window film consists of a layer or layers of thin polyester adhesive film, which is applied to the inside surface of the glass to improve impact resistance, and also to hold loose shards of glass together when the glass is broken by an impact.
Such applied window films will reduce bomb blast injuries, since the film holds the loose shards together and the whole window pane will drop to the ground as one piece rather than hundreds of cutting shards. Similarly, such films are extensively used in schools and hospitals to resist falling body impact, e.g. where persons trip and fall against non safety-rated glass. The glass shatters, but it does not disintegrate into multiple shards, because the applied window film holds the shards together.
Thicker and stronger films are used to improve smash and grab resistance of retail shop windows. However, it is possible to gain entry by using a lever bar to prise the glass and film away from the edge of the frame, thus creating a hole to allow entry therethrough, e.g. smash and grab or forced entry.
When applied window film is fitted to the inside face of the glass of a window or door, a gap is usually left around the edge of the pane where the film is trimmed against the frame. This means that the glass and applied window film can drop out of the window or door frame if enough force is applied. After bomb blasts it is common to see complete glass sheets with applied film lying inside a building.
It is known to apply the film to the pane so that it overlaps the surrounding frame and to use a beading or profile to clamp the overlapping film to the surrounding frame. Although this does increase the security of the pane against impact considerably, there is a tendency for the film to stretch and tear along the edge of the profile during an impact. Furthermore, where the profile has a gasket engaging the film on the pane, there is also a tendency for the gasket to be pulled out by the film as it stretches during an impact.
An object of the present invention is to provide apparatus and a method for securing a pane of a window or door against impact and avoiding the above-described disadvantages.
The present invention provides apparatus for securing a pane of a window or door against impact comprising an adhesive film for covering the pane and overlapping a frame surrounding the pane and a clamping profile comprising a first elongate side portion attachable by fixing means therethrough to the surrounding frame to clamp the overlapping film, and a second elongate side portion having a gasket protruding therefrom for cushioning impact movement of the pane and film, wherein the first and second elongate side portions are substantially at right angles to each other and are connected by an elongate curved portion of the profile so as to provide substantially continuous support for the film from the first elongate side portion to the gasket during an impact on the pane and thereby minimise the risk of a tear of the film during impact, the outer surface of the curved portion of the profile having a radius of curvature from 4 mm to 15 mm.
The invention further provides a window or door having a pane and apparatus securing the pane against impact comprising an adhesive film covering the pane and overlapping the surrounding frame and a clamping profile compising a first elongate side portion attached by fixing means therethrough to the surrounding frame to clamp the overlapping film, and a second elongate side portion having a gasket protruding therefrom for cushioning impact movement of the pane and film, wherein the first and second elongate side portions are subtantially at right angles to each other and are connected by an elongate curved portion of the profile to minimise the risk of tearing of the film during an impact on the pane, the outer surface of the curved portion of the profile having a radius of curvature from 4 mm to 15 mm.
The invention still further provides a method of securing a pane of a window or door against impact using an apparatus for securing a pane of a window or door against impact comprising an adhesive film for covering the pane and overlapping the surrounding frame and a clamping profile comprising a first elongate side portion attachable by fixing means therethrough to the surrounding frame to clamp the overlapping film, and a second elongate side portion having a gasket protruding therefrom for cushioning impact movement of the pane and film, wherein the first and second elongate side portions are substantially at right angles to each other and are connected by an elonge curved portion of the profile so as to provide subtantially continuous support for the film from the first elongate side portion to the gasket during an impact on the plane and thereby minimise the risk of tearing of the film during impact, the outer surface of the curved portion of the profile having a radius of curvature from 4 mm to 15 mm. The method of securing comprises covering the pane and overlapping the surrounding frame with the adhesive film, positioning the clamping profile on the surrounding frame so that the gasket abuts against the film on the pane and the first elongate side portion to the surrounding frame by fixing means therethrough so as to clamp the overlapping film against the surrounding frame.